SMAC also had 10/10 flavor text and setting overall. It's a game that has a lot of character.
I learned the word Atrocity from Sid Meier's Alpha Centauri
My dad and I had a horrible discussion in the car about the word, eventually.
"Dad, what's an atrocity?"
"It's when someone does a horrible thing to a lot of people"
"...but sometimes they're necessary, right?"
"..."
Are we still talking about Caesar chopping off all those rebellious Gauls' right hands?
> “He held his arm too stiffly, and so was thrown back repeatedly, until at last I seized his forearm and snapped it back against itself. His training suffered while the arm healed, of course, but I felt this was a lesson he must learn early, and well.”
I know that my brother had difficulty with this quote. The mental image of someone's arm being jui-jitsu'd off is pretty powerful. My brother would click "OKAY" as fast as possible to avoid listening to the quote.
It's very much trying to be a spiritual successor, but I'm not sure it really achieves the goal. The setting isn't as convincing (it's mostly Civ 5 in space, with orbital units). The factions all pretty much play the same, just with some bonuses. The biggest problem (though I suppose this has been a problem for all civ games to some extent) is that the AI is bad. It can do tactical decisions, but strategic big-picture it seems to have no clear goal.
It's worth checking out, but it's only partly the spiritual successor to SMAC it tries to be. I see a lot of people here recommending Stellaris, I haven't tried it but now I think I should.
Civ 5 wasn't bad, but I'd rather take on Auriga in Endless Legend if I'm playing a hexagonal 4X - plus it reminds me pleasantly of Master of Magic.